ML20154M383

Forwards Two Draft Repts Re Technical Insights Gained from Pras,For Info & Comments.Repts Discuss Insights on Plant Strengths & Weaknesses Gained from PRAs & Insights Into PRA Methodologies.W/O Encls

ML20154M383
Person / Time
Site:	Mcguire, McGuire
Issue date:	03/05/1986
From:	Youngblood B Office of Nuclear Reactor Regulation
To:	Tucker H DUKE POWER CO.
References
NUDOCS 8603140164
Download: ML20154M383 (3)

Text

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v Docket Hos. 50-369 and 50-370 MAR 0 51986 Mr. H. B. Tucker, Vice President Nuclear Production Department Duke Power Company 422 South Church Street Charlotte, North Carolina 28242

Subject:

Reports on PRA Insights - McGuire Units I and 2 Enclosed are two draft reports concerning technical insights gained from Probabilistic Risk Assessments (PRAs). These reports are the outcome of an ongoing effort to make available and utilize in numerous technical and managerial activities the information in PRAs regarding the factors which dominate the risk associated with nuclear power plants. This effort includes identification of the features of design or operational practices which have been found to be important to safety in the types of plants which have been subjected to risk assessments. In addition, the section on insights into PRA methodologies focuses on areas which are sansitive to the results and the overall perception of plant weaknesses and vulnerabilities.

In particular, these reports contain discussions of: general insights on plant strengths and weaknesses gained from PRAs; the contribution to core melt frequency from classes of sequences induced by various initiating events; modifications, both hardware and procedural, which have been implemented to address problems identified in the conduct or as a result of PRAs; insights into PRA methodologies; and the contribution to measures of risk (core melt frequency and consequences of radioactive releases) from systems, components and events.

These reports are being provided to you, as well as all other licensees, in advance of formal publication for your infonnation. Your comments and suggestions are welcome on these reports.

Sincerely, gginal sifD **

p. Hood O B. J. Youngblood, Director PWR Project Directorate #4 Division of PWR Licensing-A, NRR

Enclosures:

As stated cc w/o enclosure:

See next page D3d dh PWR#4: PWR-A PWR#4:DPWR-A PWR#4:DPWR-A MDbtf88 :kab DHood BJYoungblood 03/q/86 03/ /86 03/ /86 8603140164 860305 PDR ADOCK 05000369 P PDR m

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. MAR 0 51986 Mr. H. B. Tucker Duke Power Company McGuire Nuclear Station cc:

Mr. A. Carr Dr. John M. Barry Duke Power Company Department of Environmental Health P. O. Box 33189 Mecklenburg County 422 South Church Street 1200 Blythe Boulevard Charlotte, North Carolina 28242 Charlotte, North Carolina 28203 Mr. F. J. Twogood County Manager of Mecklenburg County Power Systems Division 720 East Fourth Street Westinghouse Electric Corp. Charlotte, North Carolina 28202 P. O. Box 355 Pittsburgh, Pennsylvania 15230 Chairman, North Carolina Utilities Comission Mr. Robert Gill Dobbs Building Duke Power Company 430 North Salisbury Street Nuclear Production Department Raleigh, North Carolina 27602 P. O. Box 33189 Charlotte, North Carolina 28242 Mr. Dayne H. Brown, Chief Radiation Protection Branch J. Michael McGarry, III, Esq. Division of Facility Services Bishop, Liberman, Cook, Purcell Department of Human Resources and Reynolds P.O. Box 12200 1200 Seventeenth Street, N.W. Raleigh, North Carolina 27605 Washington, D. C. 20036 Senior Resident Inspector c/o U.S. Nuclear Regulatory Comission '

Route 4, Box 529 Hunterville, North Carolina 28078 Regional Administrator, Region II U.S. Nuclear Regulatory Commission, 101 Marietta-Street, N.W., Suite 2900 Atlanta, Georgia 30323

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L. L. Williams Operating Plants Projects Regional Manager Westinghouse Electric Corporation - R&D 701 P. O. Box 2728 Pittsburgh, Pennsylvania 15230 S

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